What's the noun for concertantes? Here's the word you're looking for.
concert
(uncountable) Agreement in a design or plan; union formed by mutual communication of opinions and views; accordance in a scheme; harmony; simultaneous action.
(uncountable) Musical accordance or harmony; concord.
(countable) A musical entertainment in which several voices or instruments take part.
“Many of them are bootlegs made by a sneaky soundman or concertgoer and are of a quality dubious enough to repel the casual listener.”
“In truth, it should have been named for Truman, perhaps the most avid concertgoer in Presidential history.”
“The average concertgoer, the report said, coughs at 0.025 times a minute, which would work out at 36 coughs on average a day, double the normal average.”